Wet-dry vacuum cleaning apparatus is per se known. Apparatus of the general type involved herein is disclosed in U.S. Pat. No. 4,333,203. The apparatus as disclosed in said patent suffers from several drawbacks.
In the apparatus disclosed in said patent, there is provided a container for introducing detergent or other liquids into the flowing stream of water before discharge through a nozzle. The container is partially filled with a liquid such as detergent and thereafter the remainder of the container is filled with water. In connection with the apparatus as disclosed in said patent, the mixture of water and detergent must be accomplished at some distance from the apparatus and then attached to the apparatus without spilling the mixture. When the mixture has been totally consumed, it is necessary to disconnect the container and find a faucet for more water before cleaning may continue. These features are a disadvantage.
In the apparatus as disclosed in said patent, detergent is introduced into the water lines so long as water is flowing in the water line. There are occasions where it is desired not to introduce detergent into the water line but at the same time permit water to flow through the water line. The inability to selectively permit introduction of detergent in the water line is a disadvantage of the apparatus disclosed in said patent.
It is desirable to make the front face of the head from a transparent material such as a polymer plastic. As a result thereof, the user may judge the effectiveness of the apparatus by the color of the water being sucked into the vacuum tube. It is known to removably attach the transparent face plate with a plurality of bolts or screws. If the water is dirty, it leaves a film on the inner surface of the front face which in turn detracts from the advantage to the user on the next occasion. Hence, there is a need to have a transparent front plate on the head which is easily removable for cleaning without the necessity of tools.
The present invention is directed to a solution of the above-mentioned problems and disadvantages of the prior art.